Casting (type conversion)

Casting is the temporary conversion of one data type to another. It is required when a value’s current type is not suitable for an operation.
It allows for operations between different data types, and ensures we get user input in the correct type.
User input is usually stored as text (string), even if it looks like a number, but mathematical operations cannot be performed on strings, so casting ensures data is in the correct format for processing.
For example, in Python:

# Convert string input to integer

age = int(input(“Enter your age:”))

# Convert integer to string

age_str = str(age)

# Convert string input to integer

price = 4.99

whole_price = int(price) # 4

Explicit casting is when the programmer manually converts a data type using a function like int(), float(), str(), or bool().
Implicit casting happens automatically without programmer instruction (e.g. combining an integer and a float results in a float).
Numerical calculations require input to be cast to int or float. Failure to cast correctly can cause runtime errors.
Numbers must be cast to strings when combining with text. This prevents type mismatch errors during output.
Value errors occur when conversion is not possible (e.g. text to number).
For Boolean values, non-zero numbers usually convert to True, and zero or empty strings convert to False.

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